It is becoming more common to replace a missing tooth with a prosthetic tooth that is placed upon and attached to a dental implant. Dental implants are often comprised of metal and metal alloys, including titanium (Ti) and titanium alloys. The dental implant serves as an artificial root that integrates with the gingiva and the bone tissue of the mouth.
For the dental implant to function successfully, sufficient osseointegration is required. In other words, a bond between the implant and the bone must be formed and retained. The surface of the implant may be roughened to help enhance the osseointegration process. Non-limiting examples of processes for roughening an implant surface include acid etching and grit blasting, which impart roughness on the surface.
Other existing techniques involve forming a generally thin (e.g., generally less than 10 microns) coating of osseointegration materials, such as hydroxyapatite (HA), other calcium phosphates, or other osseointegration compounds for forming a direct chemical compound between the implant and the bone. Plasma spraying and sputtering are two major techniques that have been used to deposit, for example, HA, onto an implant surface.
U.S. Patent Application Publication Nos. 2008/0220394, 2007/0110890, and 2007/0112353 disclose methods of discrete deposition of hydroxyapatite crystals to impart a nano-scale topography. Although effective, the disclosed processes require that a residual substance (i.e., HA crystals) be left on the surface post-processing to impart a nano-scale topography into the surface.
The present invention is directed to an improved implant having a submicron topography superimposed on dual micron topographies for improving the rate and extent of osseointegration and methods of making the same.